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39
40#include "qopengl2pexvertexarray_p.h"
41
42#include <private/qbezier_p.h>
43
44QT_BEGIN_NAMESPACE
45
46void QOpenGL2PEXVertexArray::clear()
47{
48 vertexArray.reset();
49 vertexArrayStops.reset();
50 boundingRectDirty = true;
51}
52
53
54QOpenGLRect QOpenGL2PEXVertexArray::boundingRect() const
55{
56 if (boundingRectDirty)
57 return QOpenGLRect(0.0, 0.0, 0.0, 0.0);
58 else
59 return QOpenGLRect(minX, minY, maxX, maxY);
60}
61
62void QOpenGL2PEXVertexArray::addClosingLine(int index)
63{
64 QPointF point(vertexArray.at(i: index));
65 if (point != QPointF(vertexArray.last()))
66 vertexArray.add(t: point);
67}
68
69void QOpenGL2PEXVertexArray::addCentroid(const QVectorPath &path, int subPathIndex)
70{
71 const QPointF *const points = reinterpret_cast<const QPointF *>(path.points());
72 const QPainterPath::ElementType *const elements = path.elements();
73
74 QPointF sum = points[subPathIndex];
75 int count = 1;
76
77 for (int i = subPathIndex + 1; i < path.elementCount() && (!elements || elements[i] != QPainterPath::MoveToElement); ++i) {
78 sum += points[i];
79 ++count;
80 }
81
82 const QPointF centroid = sum / qreal(count);
83 vertexArray.add(t: centroid);
84}
85
86void QOpenGL2PEXVertexArray::addPath(const QVectorPath &path, GLfloat curveInverseScale, bool outline)
87{
88 const QPointF* const points = reinterpret_cast<const QPointF*>(path.points());
89 const QPainterPath::ElementType* const elements = path.elements();
90
91 if (boundingRectDirty) {
92 minX = maxX = points[0].x();
93 minY = maxY = points[0].y();
94 boundingRectDirty = false;
95 }
96
97 if (!outline && !path.isConvex())
98 addCentroid(path, subPathIndex: 0);
99
100 int lastMoveTo = vertexArray.size();
101 vertexArray.add(t: points[0]); // The first element is always a moveTo
102
103 do {
104 if (!elements) {
105// qDebug("QVectorPath has no elements");
106 // If the path has a null elements pointer, the elements implicitly
107 // start with a moveTo (already added) and continue with lineTos:
108 for (int i=1; i<path.elementCount(); ++i)
109 lineToArray(x: points[i].x(), y: points[i].y());
110
111 break;
112 }
113// qDebug("QVectorPath has element types");
114
115 for (int i=1; i<path.elementCount(); ++i) {
116 switch (elements[i]) {
117 case QPainterPath::MoveToElement:
118 if (!outline)
119 addClosingLine(index: lastMoveTo);
120// qDebug("element[%d] is a MoveToElement", i);
121 vertexArrayStops.add(t: vertexArray.size());
122 if (!outline) {
123 if (!path.isConvex()) addCentroid(path, subPathIndex: i);
124 lastMoveTo = vertexArray.size();
125 }
126 lineToArray(x: points[i].x(), y: points[i].y()); // Add the moveTo as a new vertex
127 break;
128 case QPainterPath::LineToElement:
129// qDebug("element[%d] is a LineToElement", i);
130 lineToArray(x: points[i].x(), y: points[i].y());
131 break;
132 case QPainterPath::CurveToElement: {
133 QBezier b = QBezier::fromPoints(p1: *(((const QPointF *) points) + i - 1),
134 p2: points[i],
135 p3: points[i+1],
136 p4: points[i+2]);
137 QRectF bounds = b.bounds();
138 // threshold based on same algorithm as in qtriangulatingstroker.cpp
139 int threshold = qMin<float>(a: 64, b: qMax(a: bounds.width(), b: bounds.height()) * 3.14f / (curveInverseScale * 6));
140 if (threshold < 3) threshold = 3;
141 qreal one_over_threshold_minus_1 = qreal(1) / (threshold - 1);
142 for (int t=0; t<threshold; ++t) {
143 QPointF pt = b.pointAt(t: t * one_over_threshold_minus_1);
144 lineToArray(x: pt.x(), y: pt.y());
145 }
146 i += 2;
147 break; }
148 default:
149 break;
150 }
151 }
152 } while (0);
153
154 if (!outline)
155 addClosingLine(index: lastMoveTo);
156 vertexArrayStops.add(t: vertexArray.size());
157}
158
159void QOpenGL2PEXVertexArray::lineToArray(const GLfloat x, const GLfloat y)
160{
161 vertexArray.add(t: QOpenGLPoint(x, y));
162
163 if (x > maxX)
164 maxX = x;
165 else if (x < minX)
166 minX = x;
167 if (y > maxY)
168 maxY = y;
169 else if (y < minY)
170 minY = y;
171}
172
173QT_END_NAMESPACE
174

source code of qtbase/src/gui/opengl/qopengl2pexvertexarray.cpp